How to Insulate a Walk-Out Basement

Measure the height and width of the walls in your basement. This will help you determine the number of rigid foam panels you'll need for your insulation installation.

Place a foam panel at the corner of the basement, flush against the wall. Note the location of any obstructions or openings in the wall. Measure the location of these and make corresponding marks on your panel with a pencil. Score the surface of the panel with a sharp utility knife, guiding the knife with a straightedge to ensure a consistent cut. Snap off the excess foam with your hands after you've scored the panel.

Place a tube of construction adhesive into a caulking gun and cut off the tip of the tube with a utility knife. Apply adhesive to the back of the panel. Place the panel against the wall and hold it in place until the adhesive sets and the panel doesn't shift position.

Place your next panel in position. Trim if necessary and glue into place on the wall. Continue until you've covered all the exposed wall surfaces with rigid foam panels.

Place a tube of acrylic weatherproofing caulk into the caulking gun. Apply a bead of caulk around the edges of the panels where they've been cut for openings such as doors and windows.

Apply vinyl tape over the seams between panels to complete the job.